Sheet-fed printing machine and sheet-conveying mechanism therefor



Feb. 11, 1930. s. NIEWTON ET AL 1,746,492

SHEET FED PRINTING MACHINE AND SHEET CONVEYING MEGHANI SM THEREFOR Filed Dec. 22, 1928 s Sheets-Sheet I 1 Feb. 11,- 1930. s NEWTQN'E-rAL SHEET FED PRINTING MACHINE AND SHEET CONVEYING MECHANISM THEREFOR Filed Dec. 22, 1928 s Sheets-Sheet 2 F 1, 1930- s. NEwToN ET AL 1,746,492

SHEET FED PRINTING MACHINE AND SHEET CONVEYING MECHANISM THEREFOR Filed Dec. 22, v1928 5 Sheets-Sheet 5 Patented Feb. 11,: 1930 UNITED STATES PATENT OFFICE sAMNnW'roN, or ALrnmcnAM, AND CARL Louis SIGNORS TO rHEcoMrnNY LINo'rYrn AND MACHINERY LTMITED, or LONDON, ENG;

LAND

STERN, OF LONDON, ENGLAND, AS-

SHEET-FED PRINTING MACHINE AND SHEET-CONVEYING MECHANISM THEREFOR Application filed December 22, 1928, Serial No. 327,770, and in Great Britain January 21, 1928.

This invention relatesto sheet-fed printing machines and sheet-conveying mechanism therefor, and is particularly advantageous for use in connection with a plurality of-multicolour printing machines arranged in series or tandem for successively printing onsheets passed from one to another.

The invention comprises chain conveyors having grippers to which a sheet is transferred as it is released by the grippers of an impression cylinder of one machine of the series and-which, in turn, release it for transference to the grippers of an impression cylinderof the next machine of the series, means being provided to steady the chain grippers at the parts of their travel at which they re ceive and deliver the sheets, for assistingthe maintenance of accurate register between impressions received in therespective machines, irrespective of any variations in thelength ofathe chains intermediate the receiving 1 and delivering stations. 1

F or further assisting inthe maintenance of such register-the chain conveyoris driven both atithe receiving and deliveringstations by geared connections withthe drives ofthe respective machines, which latter mayhem geared connection with one and the samemotor, so that synchronism ofoperation of all the parts shall be ensured.

The invention will now be described by reference to the accompanying drawings in which:

Figure 1 is a diagrammatic elevation viewed fromthe gear side showing an installation embodying the-said invention, this view being broken. away and condensed;

Figure 2 is side elevation (taken from the gear side) of parts of the chain conveyor mechanism and the second impression cylinder ofthe machine A of Figure 1;

Figure3 is aplan of portion of one of the conveyor chains and parts adjacent thereto;

Figure 4; is a sectional view of portion of one of the sprockets and parts co-operating therewith, and

Figure 5 is a vertical section showingthe manner of guiding the conveyor chain.

Throughout the different figures similar letters and numerals'are used to indicate like i tandem, with the aforesaid sheet conveyor 0 extending overhead, to transfer the sheets from the second impression cylinder 1 of the machine A, to the first. impression cylinder 2, ofthe machine B. i

The grippers 3 of the conveyor C have their shafts pivotally mounted in bars 4 extending transversely of the machine from one to another of two endless parallel chains 5, each of which passes around two sprockets 6, 6 Whose pitchcircles are of the same diameter as are the respective impression cylinders 1, 2. The chain and sprockets at the gear side of the installation are replicas of those at the feeder side and therefore, forconvenience of illustration, only those at the gear side have been represented in the drawing. 1

Each of the sprockets 6, 6 is driven by gearing connected with: the "drive ofthe respective impression cylinder 1 or 2; for em ample, as shown in dotted lines in Figure 1, the sprockets 6, 6*, may be in geared connection with the gear 7 ofthe respective transfer cylinder 8 by which sheets are transferred from the first impression cylinder 9 to the impression cylinder 1 of the machine A, and from cylinder 2 to cylinder 10 of machine B, the cylinders 1, 8, and 9 being intergeared, and similarly so with the cylinders 2, 8 and 10, as ordinarily in the type of machine under consideration. The receiving and delivering of the sheets by the conveyor grippers 8:is effected whilst those parts of the chains at which said grippers are carried, is passing round the sprockets 6, 6 Thus, in Figure 2, the grippers 3 are shown at theinstantat which they are taking a sheet from the impression cylinder 1 whose grippers 11 are, atthe same time, releasing the sheet.

In the constructional form illustrated, the

nd machine B, while that cylinder is in its,

raised position before it commences to fall to receive the impression.

It is a special feature of the invention that the gripper-carrying bars 4, shall be positive- 1y locked to the sprockets 6, 6, during the riods at which the sheets are transferred rom the grippers 11 of the unit A to the chain grippers 3, and from said chain grippersto the "rippers of the first impression cylinder 2 of the unit B, so that registration of the impressions will always be assured irrespective of any variations which may occur in the lengths of the conveyor chains. In the construction illustrated, this result is attained in the following manner.

The ends of the gripper-carrying bars 4, as shown in Figure 3, are rigidly secured as by bolts 12, to brackets 13 constituting links,

or inserted as links of the chains 5, these brackets bein arranged to engage in peripheral angu ar recesses 14 specially provided for their reception, in the sprockets 6, 6'. On the outer sides of the brackets or links 13, there are provided projections 'or lugs. 15, adapted to be engaged by jaws 16 pivoted to the respective sprockets 6, 6 and engaging said lugs under the influence of springs 17. As shown best in Figure 2 the jaws consist of two scissor-like members or levers which engage the lugs 15, by their outer ends, while their inner ends are furnished with rollers 18 engaged by the stationary cams 19 by which these ends, during the rotation of the sprockets, are moved apart antagonistically to the springs 17 which latter are attached to the said members between the rollers 18 and the pivots 20.

The chain grippers 3 are, as ordinarily,

closed upon their pads 21 by torsion springs 22, Figure 4, encircling their shafts 23, and opened through rollers 24 on their arms 25, travelling over or around stationary cams 26, while the grippers 11 of the two impression cylinders 1, 2 are,also, as ordinarily, closed on their pads 27 by springs (not shown in the drawings) and opened through stationary cams 28, the cams 26 and 28 being so located as to secure the before mentioned timed-cooperation of the grippers 3 and 11.

- as shown in Figure 1, travel over a plurality of idlers 32 (preferably sprockets) and under another idler 33 which can be adjusted for taking up any slack, the intervening portions of this upper flight, if desired, being .guided -66 between fixed rails and rollers similarly to the manner before described in relation to each of the lower flights.

Having described our invention, we declare that what we claim and desire to secure by Letters Patent is 1. In sheet conveying mechanism for printing machines, the combination of grippercarrying chains, brackets constituting links of said chains, bars rigidly attached to said brackets, sheet grippers mounted on said bars, sprockets adjacent to the sheet-receiving and sheet-delivering stations around which the gripper-carrying chains pass, and scissor like members pivoted on studs rotating with the sprockets, adapted automatically to lock the gripper-carrying bars to the sprockets at the time at which the grippers receive or deliver a sheet.

2. In sheet for conveying mechanism printing machines, the combination of gripper-carrying chains, brackets constituting links of said chains, bars rigidly attached to said brackets, sheet grippers mounted on said bars, sprockets adj accnt to the sheet-receiving and sheet-delivering stations around which the gripper-carrying chains pass, peripheral recesses in the sprockets for receiving the brackets, lugs on the brackets, jaws pivoted on studs rotating with the sprockets, adapted to grip the lugs to hold the brackets in the recesses, and means adapted to eflectautomatically such engagement, and the subsequent release of the lugs, when a sheet is being taken or released by a gripper.

3. In sheet conveying mechanism for printing machines, the combination of sheet grippers, chains carrying said grippers, sprockets adjacent to the sheet-receiving and sheetdelivering stations around which the grippercarrying chains pass, rigid rails located between the sprockets for guiding the lower flights of the chains, rollers adapted to hold the chains in sliding contact with said rails, and scissor-like members pivoted on studs rotating with the sprockets, adapted automatieally tolock the grippers to the sprockets at the time at which they receive or deliver a sheet.

4. In sheet conveying mechanism for printing machines, the combination of sheet grippers, chains carrying said grippers, sprockets adjacent to the sheet-receiving and sheetdelivering stations around which the grippercarrying chains pass, rigid rails located between the sprockets for guiding the lower flights of the chains, rollers adapted to hold the chains in silding contact with said rails, idlers adapted to guide and tighten the upper flights of the chains, and scissor-like members pivoted on studs rotating with the sprockets, adapted automatically to lock the grippers to the sprockets at the time at which they receive or deliver a sheet.

5. The combination with two printing units arranged in tandem for successively printing on sheets passed from one to the other and each embodying an impression cylinder provided with grippers to retain the sheets thereon during printing, of sprockets adjacent to the impression cylinders of the respective printing units, endless chains passing around said sprockets, sheet grippers carried by said chains, and scissor-like members pivoted on studs rotating with the sprockets, adapted automatically to lock the chain-carried grippers to the sprockets when receiving a sheet from or delivering a sheet to the grip-' pers of the respective impression cylinder.

6. The combination with two printing units arranged in tandem for successively printing on sheets passed from one to the other and each embodying an impression cylinder provided with grippers to retain the sheets thereon during printing, of sprockets adjacent to the impression cylinders of the respective printing units, endless chains passing around said sprockets, sheet grippers carried by said chains, gear connections between the printing units and the respective sprockets by'which the latter are driven and scissorlike members pivoted on studs rotating with the sprockets, adapted automatically to lock the chain-carried grippers to the sprockets When receiving a sheet from or delivering a sheet to the grippers of the respective impression cylinder.

i 7. The combination with two printing units arranged in tandem for successively printing on sheets passed from one to the other and each embodying an impression cylinder provided with grippers to retain the sheets thereon during printing, of sprockets adjacent to the impression cylinders of the respective printing units, endless chains pass* ing around said sprockets, brackets constituting links of said chains, bars rigidly attached to said brackets, sheet grippers mounted on said bars, peripheral recesses in the sprockets for receiving the brackets, lugs on the brackets, jaws pivotally mounted on and rotating with the sprockets adapted to grip the lugs to hold the brackets in the recesses, and means adapted to effect automatically such engagement, and the subsequent release of the lugs, when a sheet is being taken from or transferred to the grippers of an impression cylinder.

8. The combination with two printing units arranged in tandem for successively printing on sheets passed from one to the other and each embodying an impression cylinder provided with grippers to retain the sheets thereon during printing, of sprockets adjacent to the impression cylinders of the" respective printing units, endless chains passing around said sprockets, rigid rails located between the sprockets for guiding the lower flights of the chains, rollers adapted to hold the chains in sliding contact with said rails, idlers adapted to guide and tighten the upper from or delivering a sheet to the grippers of p the respective impression cylinder.

In testimony whereof we have aflixed our signatures hereto.

SAM NEWTON. CARL LOUIS STERN. 

